Field of the Invention
The present disclosure relates to a back light unit and a display device.
Description of the Related Art
With the progress of the information-oriented society, various demands for display devices for displaying an image are increasing. Recently, various kinds of display devices such as a liquid crystal display (LCD) device, a plasma display panel (PDP) device, an organic light emitting diode (OLED) display device, etc. have been used.
Of the above-described display devices, an LCD device includes an array board including a thin film transistor as a switching element for ON/OFF control of each pixel domain, an upper substrate including a color filter and/or a black matrix, a display panel including a liquid crystal layer and formed therebetween, a driver configured to control the thin film transistor, a back light unit (BLU) configured to provide a light to the display panel, etc. In the LCD device, alignment of the liquid crystals in the liquid crystal layer is adjusted depending on an electric field applied between a pixel (PXL) electrode and a common voltage (Vcom) electrode provided in the pixel domain, so that the light transmittance is adjusted and an image is displayed.
Such an LCD device needs a back light unit configured to provide a light from the outside. The back light unit includes a light source device, a light guide panel, a reflector, a cover bottom, etc.
A conventional light source device has a structure in which a plurality of light source packages is disposed on a light source mounting board. In this structure, the light source packages are positioned adjacent to alight guide panel. Herein, in order to suppress damage to the light source packages caused by thermal expansion of the light guide panel, the conventional light source device includes an attenuator, such as a T-pad, positioned between the light source packages.
Such a T-pad limits a region where the light source packages can be disposed, and, thus, limits the total quantity of light of the back light unit to a certain extent.
Further, the T-pad may cause a certain optical gap between the light source packages and the light guide panel, so that the efficiency of light transferred from the light source to the light guide panel may be decreased.